Wet spinning processes for fibers with a liquid extraction and washing apparatus are disclosed in U.S. Pat. Nos. 3,996,321 and 3,940,955. In these processes, after the coagulating liquor exits the coagulating zone, the liquid accelerates due to gravity. Once the coagulating liquor exceeds the spinning speed, filaments are usually drawn by the higher speed liquor. This causes poor control of the coagulating liquor and creates loops in the fiber, which affects spinning continuity.
One strategy for minimizing the problem discussed in the previous paragraph when spinning an acidic solution of an aromatic polyamide is to spin the fiber downward through a non-coagulating fluid into a coagulating bath and subsequently through a spin tube is taught by U.S. Pat. Nos. 4,965,033, 4,728,473, 4,298,565, 4,078,034, and 4,070,431. It can be difficult, however, to string up yarn through a spin tube, especially with long spin tubes that are needed in some processes.
Thus, there is a need in the art for an improved spin process that avoids the aforementioned problems.